Sovtek Mig 60

[xenophobe]

Is it set up for 12ax7's or is it still using those rare Russian tubes? I used to have a pair of Red Bears, which were basically import versions of the Sovtek, imported by Gibson. The Red Bear cabs were brutally well built and USA made. I sold the amps because I couldn't get the thing to sound brutal enough so I got a Mesa head.

[tomanyjacksons]

I had all JJ tubes in mine 6L6GC power and ECC83 pre. I will admit that the clean which was just the dirt pedal shut off wasn't all that clean. I love mine. Glad yours is a homerun.

[straycat]

It has ECC83S's in the pre so I may change one to a 12AT7 to lower the gain a bit.
I wouldn't call it super clean more like a pushed Fender clean changing some pre tubes might help.

[straycat]

Love to find a Red Bear 4X12 someday.

[straycat]

I have some feelers out with my amp guy to see if he can find some old NOS Sovtek tubes that would have been in these.

[Cygnus X1]

12AT7 isn't a good tube for tone, but it is a great phase inverter.
12AU7, AY7's are worth a try.

[straycat]

Thanks Cyg I need to figure out what was used when they came out.

[Cygnus X1]

I believe it was (3) 12AX7's.
But I can't find the designation for V3.

Schem scan:

http://web.aoct.org/marshall/Mig60.jpg

[DonP]

I love reading schematics.

V1 and V2 are labelled at 12AX7, but not V3. The phase inverter is the same long tailed pair circuit that Marshall uses, so I'd do a 12AX7 in V3.

A 12AT7 would be a step in the Fender direction (ala the Bassman amp that Marshall copied from), which may be good depending on what you like.

[straycat]

I would love to get a less gainy tone and more chime.
I know some JJ's are rebranded tubes some from China some are Sovtek how can you tell?

[Cygnus X1]

No reason to believe Sovtek is the best tube for this.
In reality although the circuit design is good, these amps used
inexpensive components.

Try some NOS Mullard 12AX7A's or 5751's if you have them.
Or RCA.

[Cygnus X1]

I love reading schematics.

V1 and V2 are labelled at 12AX7, but not V3. The phase inverter is the same long tailed pair circuit that Marshall uses, so I'd do a 12AX7 in V3.

A 12AT7 would be a step in the Fender direction (ala the Bassman amp that Marshall copied from), which may be good depending on what you like.

Did you see the power/filament/bias supply?
THREE sets of full wave bridge diodes!



That thing must be quiet as a church mouse.

[Hellbat]

If you want some reasonably priced good pre-tubes, I've had fantastic results with the Mesa Boogie SPAX7A's in my amp and they run around $12each brand new.

[straycat]

It is very quiet Cyg.
From the info I found these were built in an old military plant out in Siberia.Supposedly of left over military components.
The mig 60 is said to be one of the only true PTP amps they made except for the original mig 50's that had the PT's that sagged so they ended up referring to the early ones as mig 30's.
Got stronger PT's and sold them as mig 50's.

[straycat]

Called my amp guy and he has some 12AU7's and 12AY7's He said they are about 70% of a 12AX7 and would help lower the gain some.
He said you were right on the money Cyg.